Vacuum roll



w. c. NASH Jan. 20, 1942.

VACUUM ROLL Filed Jan. 11, 1939.

Patented Jan. 20, 1942 VACUUM ROLL William C. Nash, Neenah, Wis., assignor of onefourth to Mary Jones, Neenah, Wi s., one-fourth to William M. Nash, Mcnasha, Wis., one-fourth to Roy A. Nash, Bronxville, N. Y., and onefourth to Marie Duvall Nash, Neenah, Wis.

Application January 11, 1939, Serial No. 2 50,295

4 Claims.

This invention relates to improvements in suction rolls, particularly suction rolls having screen surfaces utilizable in paper making machines and similar mechanisms.

Wherever suction rolls having screen surfaces are used. for instance, in paper making operations, the screen surface of the roll is brought into rolling contact with a web of paper, a blanket or paper forming wire. Under the influence of the suction there is considerable pressure exerted between the contacting surfaces, i. e., the roll surface and web, blanket or wire surface, and there is a tendency for the screen roll surface to creep, that is, move longitudinally with respect to. the roll axis.

One of the objects of my invention is to minimize this creeping tendency by a novel suction roll construction.

Briefly described my invention comprises a skeleton suction roll around which a spiral rib is formed, the angle of pitch of the spiral being reversed at the longitudinal center of the roll, upon which the surface screen is carried.

from one another. Each spider l3 comprises an annular ring having a plurality of openings ll provided in its face whereby vacuum established within box 3 is uniformly transmitted to all parts of the interior of the roll. The periphery of each upon the spiralled ribs l6 whereby a foraminated Other objects and advantages of my invention I will be apparent from the accompanying drawing and following detailed description.

In the drawing, I

Fig. 1 is a top plan view of a suction box in which my suction roll is used.

Fig. 2 is an elevational view, parts being broken away, of my improved suction roll.

Fig. 3 is a cross-sectional view of the suction roll shown in Fig. 2.

Referring in detail to the drawing, I indicates a suction box in which my improved suction roll 2 may be used. The suction box I comprises an which a portion of the surface of roll 2 protrudes.

The ends of box 3 are provided with opposite openings through which shafts 1 and 8 extend,

the openings being sealed by means of packing glands 9. Bearings l0 are mounted upon platform H, which also carries box 3, shafts I and 8 being journalled in said bearings.

Roll 2 is carried by shafts l and 8 which are connected at opposite ends of tubular member [2 which constitutes the core of the roll. A plurality of spiders l3 are mounted upon the tubular memsurfaced roll is provided.

As has been hereinbefore described, roll 2 is adapted to be positioned within suction box 3 and a portion of its surface is adapted to protrude through the opening 5. The surface of the roll extends above the surface of the cover and is effectively prevented. This, of course, is conducive to long life of the roll surface which normally wears out very quickly.

The suction box 3 may, if desired, be utilized in conjunction with the removal of water from felts used on paper making machines. In case of such use the roll may be employed without the screen cover IT, in which event the felt rides upon the spiralled wire surface. The oppositely pitched spirals tend to cause ,the felt to track properly and in addition the oppositely pitched spirals tend to stretch the felt transversely opening up the poresof the felt at the time when the felt is being subjected to vacuum. This, of course, greatly facilitates the removal of moisture .from the felt.

If the roll is used as a suction roll for felts, the spiral ribs l6 may be separated a greater distance from each other, that is, the pitch may.

be greater than if the roll is to be covered by the ber l2, said spiders being appropriately spaced screen H. The suction roll thus used will greatly increase the life of the felts. It may be employed with a shower to thoroughly clean the felt. By its use a denser felt may be used with the assurance of lack of filling and'longer life. The spiral ribs keep the felt open and. thus free to couch water at the presses.

I claim as my invention:

1. A substantially hollow vacuum roll for use in conjunction with a suction box of the type having an opening in its upper surface through which a portion of the roll surface protrudes and over which a flexible web passes, comprising a core, a roll skeleton carried by said core, spiral ribs carried on the periphery of said roll skeleton, said spiral ribs being pitched in one direction only from an intermediate portion of said roll to an end thereof, and being pitched in the opposite direction only from said intermediate portion to the opposite end of the roll, the loops of said spiral ribs being spaced to provide communication into the interior of the roll.

2. A substantially hollow vacuum roll for use in conjunction with a suction box of the type having an opening in its upper surface through which a portion of the roll surface protrudes and over which a flexible web passes, comprising a core, a roll skeleton carried by said core, spiral ribs carried on the periphery of said roll skeleton, said spiral ribs being pitched in one direction only from an intermediate portion of said roll'to an end thereof, and being pitched in the opposite direction only from said intermediate portion to the opposite end of the roll, the loops of said spiral ribs being spaced to provide communication into the interior of the roll, and a foraminated surface member carried upon and covering said spiral ribs.

3. A substantially hollow vacuum roll for use in conjunction with a suction box of the type having an opening in its upper surface through which a portion of the roll surface protrudes and over which a flexible web passes, comprising a core, a roll skeleton carried by said core comprising a plurality of spiders mounted upon said core in spaced relation, a plurality of longitudinal ribs carried upon said spiders, spiral metallic ribs carried upon said longitudinal ribs, said spiral ribs being pitched in one direction only from an intermediate portion of said roll to an end thereof, and being pitched in the opposite direction only from said intermediate portion to the opposite end of the roll, the loops of said spiral ribs being spaced to provide communication into the interior of the roll.

4. A substantially hollow vacuum roll for use in conjunction with a suction box of the type having an opening in its upper surface through which a portion of the roll surface protrudes and over which a flexible web passes, comprising a core, a roll skeleton carried by said core comprising a plurality of spiders mounted upon said core in spaced relation, a plurality of longitudinal ribs carried upon said spiders, spiral metallic ribs carried upon said longitudinal ribs, said spiral ribs being pitched in one direction only from an intermediate portion of said roll to an end thereof, and being pitched in the opposite direction only from said intermediate portion to the opposite end of the roll, the loops of said spiral ribs being spaced to provide communication into the interior of the roll, and a foraminated surface member carried upon and covering said spiral ribs.

WILLIAM C. NASH. 

